code: def register():
      # Register this with gym.
      (
          unused_tictactoe_id,
          unused_tictactoe_env,
      ) = gym_utils.register_gym_env(
          "tensor2tensor.envs.tic_tac_toe_env:TicTacToeEnv",
          version="v0",
      )
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import gym
  from gym import spaces
  from gym.utils import seeding
  import numpy
  from tensor2tensor.data_generators import problem
  from tensor2tensor.layers import modalities
  from tensor2tensor.rl import gym_utils
label_desc: Use image node_id 5 for calling a global function with example usage: register() without return types